blush: [OE] Modern English blush is a descendant of Old English blyscan ‘turn red, blush’, which was related to and perhaps derived from Old English blysa ‘firebrand, torch’. Similarities of form and meaning make it tempting to compare blaze, which meant ‘torch’ in Old English and came from a prehistoric Germanic *blasōn, but no connection has ever been established. Middle Dutch blosen ‘glow’ may be an intermediate form. [blush etymology, blush origin, 英语词源]